HVAC Plenums and Ducts in Unconditioned Space Insulated to R-8

HVAC Plenums and Ducts in Unconditioned Space Insulated to R-8

Intent

To prevent condensation on the outside of cold HVAC ducts located in unconditioned basements and crawlspaces that can lead to moisture problems in those areas.

Additional Information/How to Implement

After sealing ductwork, use spray foam or wrap a flexible insulation product (e.g., reflective insulation, fiberglass batts) around metal supply ducts, plenums and trunks in basements and crawlspaces. Do not use flexible ductwork in crawlspaces, as it can be an entry point into the home for vermin.

Duct insulation should be in full contact with the duct unlike the image below from

http://www.mme.state.va.us/de/energybook/hbchap5.html

The image below shows properly installed duct insulation from

http://www.mme.state.va.us/de/energybook/hbchap5.html